Enter the following at the "Press Start" screen.
Performance parts 1:
Press L, R, L, R, Left, Left, Right, Up.
Performance parts 2:
R, R, L, R, Left, Right, Up, Down.
Visual parts 1:
Press R, R, Up, Down, L, L, Up, Down.
Visual parts 2:
Press L, R, Up, Down, L, Up, Up, Down.
Enter the following codes at the Main Menu:
$1000 Cash for Career Mode & RX-8 and Skyline for Quick Race:
Press Left, Left, Right, X, X, Right, L, R.
Get the Hummer H2 Capone:
Press Up, Left, Up, Up, Down, Left, Down, Left.
Get the Burger Kin Vinyl:
Up, Up, Up, Up, Down, Up, Up, Left.
Get the Best Buy Vinyl:
Up, Down, Up, Down, Down, Up, Right, Left.
